The Mute Swan (Cygnus olor) is a species of swan, and thus a member of the duck, goose and swan family Anatidae. It is native to much of Europe and Asia, and (as a rare winter visitor) the far north of Africa. It is also an introduced species in North America,Australasia and southern Africa. The name ‘mute’ derives from it being less vocal than other swan species.[1][2][3] Measuring 125 to 170 centimetres in length, this large swan is wholly white in plumage with an orange bill bordered with black. It is recognisable by its pronounced knob atop the bill.
The Mute Swan was first formally described by the German naturalist Johann Friedrich Gmelin as Anas olor in 1789, and was transferred by Johann Matthäus Bechstein to the new genus Cygnus in 1803. It is the type species of the genus Cygnus.[4] Both cygnus and olormean “swan” in Latin; cygnus is related to the Greek kyknos.[5][6] The synonym Sthenelides olor has occasionally been used in the past.
Despite its Eurasian origin, its closest relatives are the Black Swan of Australia and the Black-necked Swan of South America, not the other Northern Hemisphere swans.[1] The species is monotypic with no living subspecies.[1][3]